Food blenders for domestic and commercial kitchen use typically comprise of a number of components which may be disassembled for cleaning purposes but also for servicing and the replacement of worn or damaged parts.
Typically, the main components of a food blender are a base module which houses the driving motor, its control circuitry and operator controls; a glass or at least transparent blender jug, and a blade assembly secured in the base of the jug. Some blenders at least include a transition skirt which covers the junction between the base module and the blender jug.
Again typically, the lower end of the blade shaft is splined and mates with an internally splined output shaft of the drive motor located in the base module. One or more projecting elements from the base module engage with the jug (or a skirt depending from the jug) to prevent rotation of the jug relative the base module. A safety interlock is usually also provided to prevent operation of the drive motor when the jug and blade assembly is not correctly located on the base module.
The majority of both commercial and domestic blenders have removable blade assemblies. These are removable primarily to facilitate cleaning, but also because blade assemblies do not always last as long as the blender jugs and may require replacement. The latter is especially true with glass blender jugs, which normally last longer than plastic blender jugs and can easily outlast the blending blades.
Most known removable blade assemblies are clamped to the bottom of the blender jug by means of some sort of bayonet fitting or threaded nut or member which, together with a sealing washer, secures the assembly to the blender jug. This basic system has proven to be very successful as it allows for several tolerance variations in both blade assemblies and blender jugs.
Frequently however, these locking nuts or members prove very difficult to remove by hand. In many cases they are recessed within a skirt projecting below the blender jug, so that limited purchase may be available for the hand of a user. Frequently, if not removed immediately after use, a securing nut or member is liable to seize in position.
As one solution to this problem, several manufacturers supply separate tools specifically for the undoing of these securing elements. One problem with this approach is that such separate tools are likely to be misplaced and, where the securing system has been designed to rely on such tools, a user may be left with a dirty or unserviceable blender.
Another problem with known blender assemblies is that the transition skirt is permanently attached to the blender jug. In one know arrangement, the blade assembly is locked into the skirt, for example by a bayonet connection, rather than being assembled directly to the jug. A disadvantage is that food particles and other grime can become lodged between the adjoining surfaces of jug and skirt, forming an unsightly and unhygienic ring.
It is an object of the present invention to address or at least ameliorate some of the above disadvantages.
Note
    1. The term “comprising” (and grammatical variations thereof) is used in this specification in the inclusive sense of “having” or “including”, and not in the exclusive sense of “consisting only of”.    2. The above discussion of the prior art in the Background of the invention, is not an admission that any information discussed therein is citable prior art or part of the common general knowledge of persons skilled in the art in any country.